The diversity and versatility of display devices imposes new demands on designers of digital multimedia. For example, designers must create different alternatives for web content and must design different layouts for different display devices. Also, Hyper Text Markup Language (HTML) and other standards can support dynamic changes of page layout. Typically, sizes of images or videos which are one of the core elements of digital multimedia maintain a rigid state, and cannot be modified so as to automatically fit different layouts in view of an aspect ratio of the image or video. In other cases, the size or aspect ratio of an image or video needs to be changed so as to fit different display devices, such as computers, cell phones or Personal Digital Assistants (PDAs). Also, the video may need to be shown with different runtimes for different purposes (e.g., video summarization and video editing). Further, video and image content in web pages, which are a part of a web layout, needs to be resized based on resolutions of the display devices.
Conventional technologies for image resizing typically include scaling and cropping, however, do not consider the content of an image to be resized. Such technologies are oblivious to the image content, and typically can only be applied uniformly. Also, such methods may distort the image content which may be important to a viewer. More effective resizing can only be achieved by considering the image content as a whole, in conjunction with image dimensions.
An existing method resizes an image by using seam carving. The method operates on “seams” that run from one side of the image across to the other. Removing all pixels in a seam reduces the image by one row or one column of pixels. In contrast, adding seams to the image can enlarge the image by one row or one column of pixels. When multiple seams are removed from identical areas within the image, distortions are likely to occur and be visible in the resized image. Because these and other existing technologies are computationally expensive, they cannot provide real-time performance. From all these points of view, the existing technologies are not adequate to meet the demands created by the diversity and versatility of display devices.